XR700 slow wifi

Hey guys so i have a xr700 wifi speed is amazing downstairs but as soon as i go upstairs it goes from 800mb to around 5-10mb i am drectly above the router so it is not a big distance maybe 10 meters max from the router to my phone if i was to cut a line in the floor.

enabled smart mode to bond 2.4ghz and 5ghz 

enabled implicit beamforming
enabled mu-mimo 
CTS/RTS 2347

preamble mode: auto

transmit power 100% 

if anyone has any idea or settings that could be changed let me know as iv never had an issue like this before with any other routers